Meteor that rocked Russia was a cosmic close call

Originally published February 15, 2013 at 9:06 pm

Updated February 16, 2013 at 1:44 pm

A worker sweeps up shattered glass from a store’s broken windows in Chelyabinsk, Russia. A meteor that scientists said exploded over the Ural Mountains on Friday set off blasts that broke windows and brought down walls, injuring hundreds.

MOSCOW — With a blinding flash and a booming shock wave, a meteor blazed across the western Siberian sky on Friday and exploded with the force of 20 atomic bombs, damaging buildings across a vast territory and spreading panic in a city of 1 million. Russia’s Interior Ministry said about 1,200 people were injured, 200 of them children, mostly from shattered glass.

Many of the injuries were reported in the city of Chelyabinsk, about 950 miles east of Moscow, in a region where there are many factories for defense, including nuclear-weapons production. But there was no indication of damage that resulted in any radiation leaks, officials said.

The blast was caused by a 7,000-ton meteor, of a type known as a bolide, which created a powerful shock wave when it hit the Earth’s atmosphere, the Russian Academy of Sciences said in a statement. Scientists believe the bolide exploded and evaporated at a height of 20 to 30 miles above Earth, but small fragments — meteorites — may have reached the ground, the statement said.

The governor of the Chelyabinsk district reported that material from the sky had fallen into a lake on the outskirts of a city about 50 miles west of Chelyabinsk.

The meteor came hours before a small asteroid, 2012 DA14, passed close to Earth on Friday, which NASA was tracking on its website. Alexander Dudorov, a physicist at Chelyabinsk State University, said it was possible the meteorite may have been flying alongside the asteroid.

“What we witnessed today may have been the precursor of that asteroid,” said Dudorov in a telephone interview.

Others disputed that view, saying there was almost certainly no connection. The Jet Propulsion Laboratory, part of NASA, said on its website that “preliminary information indicates that the fireball in Chelyabinsk, Russia, is not related to asteroid 2012 DA14, which is flying by Earth today.”

Professor Alan Fitzsimmons, an astronomer at the Astrophysics Research Centre at Queen’s University Belfast, told BBC that 2012 DA14 approached Earth from the south, while the meteor struck the Earth’s atmosphere in the northern hemisphere, indicating the objects were traveling in different directions.

“This is literally a cosmic coincidence, although a spectacular one,” he said.

Fiery meteors are not unusual, but they typically evaporate far above the Earth’s surface, the Russian Academy of Sciences said in its statement. This meteor was unusual because it was so hard and may have been made of iron, the statement said. Nothing similar has been recorded on Russian territory since 2002.

Video clips from the city of Chelyabinsk showed an early-morning sky illuminated by a brilliant flash, followed by the sound of breaking glass and multiple car alarms. Meteors typically cause sonic booms as they enter the Earth’s atmosphere. On Friday, the force was powerful enough to shatter dishes and televisions in people’s homes.

“I saw a flash in the window, turned toward it and saw a burning cloud, which was surrounded by smoke and was going downward; it reminded me of what you see after an explosion,” said Maria Polyakova, 25, head of reception at the Park-City Hotel in Chelyabinsk.

“There was panic. People had no idea what was happening,” said Sergey Hametov of Chelyabinsk. “We saw a big burst of light, then went outside to see what it was and we heard a really loud, thundering sound,” he told by telephone.

The shock wave blew in more than 1 million square feet of glass, according to city officials, who said 3,000 buildings in Chelyabinsk were damaged. At a zinc factory, part of the roof collapsed.

The Interior Ministry said about 1,200 people sought medical care after the shock wave and 48 were hospitalized. Most injuries were caused by flying glass, officials said.

Scientists estimated the meteor unleashed a force 20 times more powerful than the Hiroshima bomb. But because the space rock exploded at an extremely high altitude, Amy Mainzer, a scientist at NASA’s Jet Propulsion Laboratory, said the atmosphere acted as a shield.

The shock wave may have shattered windows, but “the atmosphere absorbed the vast majority of that energy,” she said.

There was no immediate word on any deaths or anyone struck by fragments from the space rock.

The government response Friday was huge. Seven airplanes were deployed to search for places where meteorites might have fallen, and more than 20,000 people were sent to comb the area on foot, according to the Ministry of Emergency Situations. There were also 28 sites designated to monitor radiation.